This invention relates generally to a microchannel heat exchanger including multiple fluid circuits.
A microchannel heat exchanger (MCHX) exchanges heat between a refrigerant and a fluid, such as air. The microchannel heat exchanger includes a plurality of microchannel tubes. The refrigerant flows through the plurality of microchannel tubes, and the air flows over the plurality of microchannel tubes.
The microchannel heat exchanger utilizes a single refrigerant circuit. The refrigerant enters the circuit through an inlet and can make multiple passes through the microchannel heat exchanger. The refrigerant then exits the circuit through an outlet. This results in a high refrigerant side pressure drop for a given amount of refrigerant side heat transfer. This adverse relationship affects the overall system performance, particularly at high outdoor ambient conditions, which causes the discharge pressure to be higher than a comparable round tube plate fin (RTPF) heat exchanger.